Variable Induction Control Valve: Description and Operation

OPERATION

The World Engine is equipped with an intake manifold flow control valve to promote maximum air/fuel atomization. The valve restricts airflow, causing it to tumble or swirl. The tumbling action helps ensure that the fuel and air mix thoroughly and burn faster. The intake manifold flow control valve and variable valve timing work together to improve fuel economy, idle stability, and emissions.

The electrically controlled intake manifold flow control valve is located in the intake manifold at the cylinder head. The intake manifold is constructed of composite material and divided into equal length runners. At the end of each runner is an intake manifold flow control valve flap. The intake manifold flow control valve actuator controls the flaps through a common shaft.

The intake manifold flow control valve actuator is a two-position torque motor that is pulse-width driven by the GPEC1. The actuator is either energized to move the flaps out of the way to the wide-open position or de-energized to move the flaps up, to a restricted position.

The intake manifold flow control valve actuator also contains a potentiometer feedback system to aid in diagnosis. The potentiometer circuit reports the actual position of the intake manifold flow control valve flaps. The GPEC1 compares the actual position with the desired position to ensure that the system is functioning correctly. The intake manifold flow control valve flaps are the mechanical components that restrict airflow to the intake ports. When the valves are moved upward, airflow is restricted and tumble occurs. When the valves are flat against the manifold, the full, unrestricted air charge flows to the intake ports.

It is energized under specific operating conditions: At high engine speeds (greater than 3600 rpm on the 1.8 and 2.0 liter or greater than 4000 rpm on the 2.4 liter) or at wide-open throttle, the intake manifold flow control valve actuator is energized and the flaps move to the wide-open position, at lower engine speeds (less than 3600 rpm on the 1.8 and 2.0 liter or less than 4000 rpm on the 2.4 liter), the actuator is de-energized allowing the flaps to remain in the restricted position. The flap is held at that position by the return spring.